Answers to Your Burning Candle Questions

We’ve been making sustainable candles in Brooklyn since 2015. Over the years we’ve gotten a lot of questions: some deep, some silly, and some that make us scratch our heads. Today we wanted to take some of your top candle questions and answer them rapid-fire style!

1. Do Candles Float in Water?

Cue the science class flashback! Here’s a handy explainer about why objects float. The short version? It’s all about density and shape. Most candles aren’t as dense as water, which makes it easier for them to stay on top. The candle also needs to have enough surface area for the water to push back. So yes, most candles can float, assuming they have the right shape.

Our candles will float, but will also tend to fall on their side in water so we do not recommend filling your bathtub with them. Sorry!

2. Will Candles Melt in the Car?

It is possible. Depending on the wax used, candles can melt anywhere between 115-150 degrees Fahrenheit. And the CDC says that the inside of a car parked in direct sunlight can get as hot as 130-172 degrees Fahrenheit! So park in the shade, and don’t leave your candles, dogs, or M&Ms in the car!

3. Do Candles Expire?

The general rule of thumb is to burn a candle within a year of opening it. While a candle can be stored for a long time, any scent or dye will eventually degrade. If you do decide to store candles, wrap them in cellophane and store them in a cool, dry place. This will keep moisture, light, and air from affecting them.

4. Why Do Candles Flicker?

When a candle is burning, it is heating the air around the wick. That warm air rises, and cool air rushes in around the base of the flame. A candle flame may flicker when first lit because the combustion reaction is stabilizing (see answer #5 below for more on the combustion process!). Any subsequent flickering is due to the flame getting too little or too much air or fuel — most likely caused by lack of ventilation or gusts of air (is that window open??).

5. When Candles Burn Where Does the Wax Go?

The wax is first melted by the heat of the flame, then it is drawn up the candle wick like water in a drinking straw. Once near the flame the wax gets so hot it turns into a gas, which then reacts with oxygen in the air — in a process known as combustion — to become water (H2O) and carbon dioxide (CO2). So ultimately, the solid wax is heated up into a liquid and then into a gas which then reacts with the air. You can read a more in-depth explanation here.

6. Where Did Candles Originally Come From?

Sometime around 3,000 B.C. the ancient Egyptians would take the cores of reeds and dip them in animal fat to create candle-like objects called rushlights. However, rushlights didn’t have wicks like modern candles. It was the ancient Romans who melted beef fat (tallow) and poured it over fibers. This combination formed the first wicked candles.

7. Are Candles Vegan?

It depends. For this article, we’ll define vegan candles as not being tested on animals or containing animal products or byproducts. Beeswax candles are not vegan. And some candles may contain stearic acid, which is used to harden the wax and make it opaque. Stearic acid can come from coconuts, but the cheaper and more common option is to get it from the meat industry.

PETA has a list of vegan candle companies. At Keap we use a small amount of beeswax in our candles to affix our wicks to the glasses without using sticky glues so that our glasses can be easily reused; we don’t use stearic acid in our products.

8. Are Candles Bad for You?

We’ve written about candle-related health concerns before. Candles can be enjoyed safely by buying U.S.-made, sticking to naturally-derived waxes (instead of paraffin), and by trimming the wick before each lighting. If you find yourself experiencing allergies, try higher quality fragrances and contact the manufacturer if you want a replacement.

9. Are Candles Allowed in Hand Luggage?

Yes! The TSA says solid candles are safe to fly in both carry-on and checked luggage. Gel candles however, will need to put in checked luggage. Most airlines also allow 1 lighter or box of matches to be carried in hand-luggage. That said, we recommend checking the baggage policies of any airline you are travelling with just to make sure; look for their policy on flammable substances.

If you do want to spruce up a candle, consider spray-painting a glass container and then placing the candle inside of that. We suggest using a paint with a low volatile organic chemical (VOC) content like Ironlak’s Sugar line.

12. How Were Candles Made in Medieval Times?

In medieval times, most people had candles made from tallow (animal fat), which was a technique first used by the ancient Romans. The problem with tallow candles was that they smelled quite bad and gave off a smoky flame. In response to this, beeswax candles were invented. They smelled pleasant and burned cleanly, They were also very expensive and were mostly used for church services and by the wealthy.

13. Which Candles Drip the Most?

There are candles specifically made to drip — mostly for that shabby-chic, melted onto a bottle look! Cheap candles too, are likely to drip. Many candles now are “dripless” which means they have an outer layer of hard wax meant to contain the pool of liquid wax created as the candle burns.

14. What Candles Are Used for Ear Candling?

Okay, we want to say that you should do your research before doing ear candling! This is an alternative medicine practice that is not approved by the FDA and considered dangerous and ineffective by the Mayo Clinic and others. It involves using a hollow candle that consists of a fabric cone soaked in wax, placing one end in the ear, and then lighting the candle. Supposedly this creates enough suction to pull wax out of the ear canal. But researchers have found no basis to these claims. We say, enjoy candles with your eyes and nose, not your ears!

15. Which Candles Repel Mosquitoes?

The short answer is none. Citronella candles are commonly sold with claims of keeping mosquitoes at bay, but research suggests that they’re no more effective than regular candles, which aren’t that effective. Your best bet is to cover your skin, spray on DEET-containing repellent, and clean up any standing water to there’s no place for the pests to lay their eggs.